5.2.1-fa164c8
Win11
I create a new transaction (in a checking or credit card account, it doesn’t matter, happens with both.) I enter in a dollar amount, select a payee, choose a category, then click on the Split button (to split the allocation between categories.)
I double click on the Payment value in the Split editor window, single line summary of the category allocations. The details expand in the window and the full amount is highlighted by default. To recreate the crash, only highlight the dollar portion of the value. For example, if the amount is 36.00, only highlight 36. Then, press the slash key on your keyboard to divide. (I expect the calculator window to appear.) The window freezes and the app crashes. Highlighting the full amount (dollars and cents) works just fine without crashing.
I confirm a similar issue with Version 5.2.1-a9da67bb9 on Linux. Selecting only the dollar amount of the payment column and then typing a “/” just freezes the program completely for me, and I can’t do anything other than kill the process. The difference is probably just in how the OS is responding to whatever funny state KMyMoney has gotten into. I also note that the same happens with the Payment amount in the main transaction editor, so I don’t think it’s actually related to the split editor.
Awesome, thanks for the confirm. Obviously this is a very low issue, the workaround being to highlight the entire dollar amount like should be done in the first place. 
This problem was introduced more than 4 years ago and results in an infinite recursive loop which causes the behavior y’all notice.
I was thinking about a fix and came to the same conclusion: if only a part of the amount is selected and one of the numeric operations (+,-,*,/,%) is pressed, then simply don’t touch the amount before opening the calculator.
has been created and fixed.